Acids, Bases and Salts - Episode 3

This is the third episode of the series on Acids, Bases and Salts. In this episode, we discuss the properties of acids and bases.

Properties of Acids

Physical Properties: 

Sour in taste.

Highly corrosive.

 Chemical Properties:
Acid (Dil.) + Active Metals*

2HCl (Dil.) + Mg = MgCl2 + H2

2Al + 6HCl = 2AlCl3 + 3H2

Salt + H2 (*Active Metals – MAZFE – Magnesium, Aluminium, Zinc, Iron) 

o Metallic (Bi)Carbonates + Acid (Dil.) Metallic Salt + CO2 + H2O

•  Na2CO3 + HCl (Dil.) NaCl + H2O + CO2

•  NaHCO3 + HCl (Dil.) NaCl + H2O + CO2

o Metallic (Bi)Sulphites + Acid (Dil.) Metallic Salt + SO2 + H2O

• Na2SO3 + HCl (Dil.) NaCl + H2O + SO2

• NaHSO3 + HCl (Dil.) NaCl + H2O + SO2

o Metallic Sulphides + Acid (Dil.) Metallic Salt + H2S (Rotten Egg Smell) o FeS + HCl FeCl2 + H2S (Rotten Egg Smell)

Properties of Bases

Neutralization: Acid + Base = Salt + Water

 HCl+NaOH = NaCl+H2O
o Ammonium Salts + Alkali = Salt + Ammonia + Water

 NH4Cl + NaOH = NaCl + NH3 + H2O

Reaction of alkalis with metal salt solutions:

• CuSO4 + 2NaOH = Cu(OH)2 + Na2SO4

  Pale blue ppt

• ZnSO4 +2NaOH = Zn(OH)2 + Na2SO4

  Gelatinous white ppt

• Zn(OH)2 + 2NaOH = Na2ZnO2 + 2H2O

• Pb(NO3)2 + 2NaOH = Pb(OH)2 + 2NaNO3

  Chalky white ppt

• Pb(OH)2 + 2NaOH = Na2PbO2 + 2H2O

• FeSO4 + 2NaOH = Fe(OH)2 + Na2SO4

  Dirty green ppt

• FeCl3 + 3NaOH = Fe(OH)3 + 3NaCl

  Reddish brown ppt